JP2002161880A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain high bearing reliance and compression efficiency, and a low oil rising quantity in a scroll compressor having structure as to support a turning scroll member with medium pressure of a back-pressure chamber. SOLUTION: In this scroll compressor, a back-pressure chamber is divided into a first space 14a under roughly discharge pressure at its central section and a second space 14b under medium pressure at its outer periphery by a sealing member. Lubricating oil 17 is led to the first space, and the second space is communicated with a compressed space 7 in the cause of compression via a small hole 11. A drain oil passage 18 opened to the first space is provided, and communicates with a drain oil pipe 19 for leading the lubrication oil 17 to its bottom section inside a sealed container 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly to a scroll compressor suitable as a refrigerant compressor for refrigeration and air conditioning, and a compressor for air or other gas.

[0002]

2. Description of the Related Art A basic structure of a general scroll compressor includes a fixed scroll member 1 in which a spiral wrap 1b standing upright on a head plate 1a is formed in a closed container 10 as shown in FIG. Upright spiral wrap 2b
The orbiting scroll members 2 formed with each other are engaged with each other with the wrap inside, the frame 3 is connected to the fixed scroll member 1, and furthermore, rotation prevention such as an Oldham ring is provided between the frame 3 and the orbiting scroll member 3. Mechanism member 4
Is provided.

When the crankshaft 6 is rotated by the rotation of the electric motor 5, the orbiting scroll member 2 engaged with the crank pin 6a makes an orbital movement with respect to the fixed scroll member 1.

[0004] Along with this orbiting movement, the gas is moved around a compression space 7 formed by the fixed scroll member 1 and the orbiting scroll member 2 to reduce the volume and compress the gas. When the compression space 7 reaches the vicinity of the center of the scroll members 1 and 2, the compression space 7 communicates with the discharge port 1 c, and the compressed gas is discharged into the closed container 10.

In the scroll compressor having such a configuration and operation, the fixed scroll member 1 and the orbiting scroll member 2
Is exerted on both scroll members 1 and 2 by the pressure of the compressed gas existing in the compression space 7. As a result, the scroll members 1 and 2 are separated from each other, and a normal compression operation cannot be performed.
Therefore, as shown in, for example, Japanese Patent Publication No. 62-37238, a gas pressure is applied to a back pressure chamber on the back side of the orbiting scroll member 2 to apply an axial pressing force to the orbiting scroll member 2. The separation of the scroll members 1 and 2 is prevented.

The back pressure chamber is pressure-coupled to the interior of the sealed container 10 by the lubricating oil supplied to the seal bearing 9 through the oil supply passage formed in the frame 3 and the crankshaft 6 and the fixed scroll member 1. In a sealed state, the back pressure chamber communicates with the compression space 7 in the middle of compression by the small hole 11 provided in the orbiting scroll member 2, so that the suction pressure and the discharge pressure follow the change of the suction pressure. It is at an intermediate pressure. Further, the lubricating oil supplied to the seal bearing 9 flows into the back pressure chamber. The lubricating oil that has flowed into the back pressure chamber is further mixed with the compressed gas in the compression space 7 through the small holes 11 provided in the orbiting scroll member 2 and discharged to the space in the closed container 10. The lubricating oil is separated from the discharge gas, but cannot be separated. This is referred to as oil rising. In particular, when downsizing the compressor or the like, a sufficient oil separation space cannot be secured in the sealed container 10, and therefore, sufficient separation is not performed and the oil rising amount increases. Would.

In the conventional compressor, the back pressure chamber is pressure-sealed by the lubricating oil supplied to the frame 3, the fixed scroll member 1, and the seal bearing 9. The space inside the sealed container 9 on the space side in the closed vessel is the discharge pressure, and the pressure on the back pressure chamber is the pressure in the back pressure chamber (intermediate pressure between the suction pressure and the discharge pressure: hereinafter referred to as the intermediate pressure). Therefore, a pressure gradient from the discharge pressure to the intermediate pressure occurs in the height direction of the seal bearing 9. When a part of the lubricating oil supplied to the seal bearing 9 flows into the back pressure chamber, the pressure gradient causes the refrigerant dissolved in the lubricating oil to foam under reduced pressure. When the refrigerant undergoes decompression foaming, the oil film formed on the seal bearing 9 is broken, and the bearing cannot perform its original function, cannot bear the bearing load, and may suffer from seizure damage of the bearing. .

The lubricating oil flowing into the back pressure chamber is supplied to the small holes 11.
, Is mixed with the compressed gas present in the compression space 7 in the middle of compression, and is discharged into the space in the closed container 10 through the discharge port 1c. In this case, lubricating oil close to the discharge temperature is mixed into the gas during compression, and the temperature of the compressed gas rises.
That is, extra compression work is required for the temperature rise, and the compression efficiency is reduced. Further, it is necessary to separate the lubricating oil mixed with the discharge gas in the closed container 10.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a scroll compressor having a structure in which a orbiting scroll member is supported by the pressure of a back pressure chamber formed on the back surface of a orbiting scroll member. Oil amount (oil rise amount)
Another object of the present invention is to provide a scroll compressor capable of reducing the number of scroll compressors.

[0010]

In order to achieve the above object, a scroll compressor according to the present invention is characterized by what is stated in claims 1 to 5, but is claimed as an independent claim. The scroll compressor according to the first aspect of the present invention provides an electric motor and a scroll compression mechanism housed in a closed container, and communicates the inside of the closed container with a discharge port to maintain the pressure in the closed container at the discharge pressure, while turning the scroll member. In a scroll compressor having a back pressure chamber on the side opposite to the lap, a seal member is provided between the frame fixed to the fixed scroll member and the orbiting scroll member. A first space having a pressure equal to the discharge pressure and having an opening of an oil supply passage through which lubricating oil stored in the bottom of the closed container is guided upward, Divided into a second space maintained at a pressure between the input pressure and the discharge pressure, the seal member is configured to be held by the frame, and the upper end surface of the seal member and the anti-wrap side surface of the orbiting scroll member And a seal between the outer peripheral surface of the seal member and the ring-shaped groove, and the sealed container without mixing the lubricating oil in the first space with the compressed gas in the sealed container. An oil drain pipe returning to the inner bottom is provided, and the lower end of the oil drain pipe is extended to the bottom of the closed vessel below the lower end of the electric motor and opened.
Further, the scroll compressor according to the second aspect of the present invention, as an independent claim, meshes the end plate, the orbiting scroll member and the fixed scroll member each formed of a spiral wrap standing upright on the end plate with the wrap inside. Together, move around the compression space formed by both scroll members,
A scroll compression mechanism that performs relative movement of the two scroll members so as to reduce the volume is housed in a sealed container, and the inside of the sealed container is communicated with a discharge port to maintain the pressure in the sealed container at the discharge pressure, while the orbiting scroll member. In the scroll compressor having a back pressure chamber on the side opposite to the lap, a seal member is provided between the orbiting scroll member and the frame, and the seal member has a pressure substantially equal to the discharge pressure in the center portion. A first space in which an oil supply passage through which lubricating oil stored in a bottom portion of the sealed container is guided upward is opened, and a second space is formed in an outer peripheral portion of the seal member; Is configured to be held by the frame, seals between the upper end surface of the seal member and the side opposite to the lap of the orbiting scroll member, and has a ring shape with the outer peripheral surface of the seal member. And a drain pipe for returning the lubricating oil in the first space to the bottom of the closed vessel without mixing with the compressed gas in the closed vessel. It is characterized in that the lower end is extended and opened to the bottom of the closed vessel below the lower end of the electric motor. The scroll compressor according to the invention according to claim 3 as an independent claim includes a head plate,
The orbiting scroll member and the fixed scroll member, each of which is composed of a spiral wrap standing upright on the end plate, are engaged with each other with the wraps inward, and are moved around the compression space formed by both scroll members to reduce the volume. As described above, the scroll compression mechanism that performs the relative movement of the two scroll members is housed in the closed container, and the inside of the closed container is communicated with the discharge port to maintain the pressure in the closed container at the discharge pressure, while the orbiting scroll member is on the opposite wrap side. In a scroll compressor having a back pressure chamber, a seal member is provided between the orbiting scroll member and the frame, and the seal member has a pressure substantially equal to the discharge pressure in the center portion and in the sealed container. Forming a first space in which an oil supply passage through which lubricating oil stored in a bottom portion is guided to an upper portion is formed; A second space is formed, and a force corresponding to a pressure difference between the first space and the second space is applied to the seal member from a lower side to an upper side, so that the upper end surface of the seal member and the orbiting scroll member are opposed to each other. In addition to sealing between the lap-side seal surface and the outer peripheral surface of the seal member and the frame, the seal is formed by the differential pressure from the first space to the second space via the seal member. An oil drain pipe is provided, which leaks a minimum necessary amount of lubricating oil and returns most of the remaining lubricating oil in the first space to the bottom of the closed container below the electric motor.

According to a fourth aspect of the present invention, there is provided a scroll compressor according to any one of the first to third aspects, wherein the scroll compressor has an opening in the first space and is provided in a closed container. An oil passage communicating with a space is formed in the frame, and a pressure head for guiding the lubricating oil to the first space is set to be higher than a minimum head necessary to reliably push up the lubricating oil to the upper end of the crankshaft; The lubricating oil that has flowed into the first space can be surely drained from the drainage passage to the bottom in the sealed container, and furthermore, according to the invention according to claim 5 as a dependent claim, A scroll compressor according to any one of claims 1 to 4, wherein a groove for holding the seal member is provided in the frame.

[0012]

According to the present invention, a very small amount of the lubricating oil which has flowed into the first space leaks into the second space through the seal member to reduce the necessary minimum amount of lubricating oil or the like to the Oldham ring. Except, most of the air is discharged into the closed container space through an oil drain in the frame that opens into the first space. Therefore, the lubricating oil discharged by the oil drain pipe and the partition plate
Since it is not mixed with the discharge gas in the space inside the closed container, a mechanism for re-separating the lubricating oil in the discharge gas can be made unnecessary, and a low oil rising amount can be achieved.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an overall structural view of a scroll compressor showing one embodiment of the present invention, and FIG. 2 is a partially enlarged view thereof. A fixed scroll member 1 having a spiral wrap 1b standing upright on a head plate 1a, and a orbiting scroll member 2 having a spiral wrap 2b standing upright on a head plate 2a.
And the fixed scroll member 2
Is connected to the frame 3 by several bolts 13. The frame 3 has a back pressure chamber on the back side of the orbiting scroll member 2.

The stator 5 a of the electric motor 5 is fixed inside the closed casing 10, and the rotor 5 b is connected to the crankshaft 6. At the end of the crankshaft 6 is a crank pin 6a
And is inserted into a boss 2 c formed at the center of the orbiting scroll member 2.

The anti-rotation member 4, such as an Oldham ring, is of a configuration known per se, and will be briefly described. The rotation prevention member 4 includes a ring portion and a key portion.
, And at least one mutually orthogonal key grooves 1d and 2d provided on the end surface of the fixed scroll member 1. Instead of the keyway 1d formed in the fixed scroll member 1, a keyway may be formed in the frame 3 as in the related art.

A seal member 15 is provided between the frame 3 and an end surface of the boss 2c as a seal surface on the back side of the orbiting scroll member 2, and a back pressure chamber 14 is provided.
Is divided into a first space 14a inside the seal member and a second space at the outer peripheral portion, and both spaces 14a and 14b are pressure-sealed. FIG. 2 is an enlarged view of this part. A ring groove 3a is formed in the frame 3 to hold the seal member 15 and to process the lower end surface of the boss portion 2c of the orbiting scroll member 2 sufficiently smoothly so that the upper end surface of the seal member 15 and the boss portion 2c are formed. By contacting the lower end surface, the first space 14a and the second space 14b in the back pressure chamber are pressure-sealed. Also, the first space is almost at the discharge pressure,
The second space has an intermediate pressure, so that the sealing member 15 receives a force corresponding to the pressure difference from the inside to the outside. That is, the outer peripheral surface of the seal member 15 and the outer peripheral surface of the ring groove 3a are also sealed. The seal member 15 is, for example, a seal ring made of a fluororesin or a polyimide resin, and may be any as long as it can obtain a necessary sealing property under the conditions inside the compressor during operation. In addition, although one example of the seal member is shown, a plurality of seal members may be used to enhance the sealing property.

When the rotor 5b of the electric motor 5 rotates, the crankshaft 6 connected thereto rotates, and the orbiting scroll member 2 inserted into the crankpin 6a makes an orbiting motion. Is moved to the center while reducing the volume, and compresses the refrigerant gas sucked from the suction pipe 8. The compressed refrigerant gas passes through a discharge port 1c provided at the center of the fixed scroll member 1, and passes through a closed container 10
It is discharged into the space inside. The discharged compressed gas is guided to the lower space of the frame 3 through a fixed scroll member 1 and a gas passage (not shown) provided on a side surface of the frame 3, and after passing through the discharge pipe 16 after cooling the electric motor 5. And sent to the point of use.

An oil supply passage 6b is provided in the crankshaft 6, and the lubricating oil 1 stored in the bottom of the closed container 10 is rotated by the rotation of the crankshaft 6 and the action of a centrifugal pump.
Guide 7 to the top. The oil supply passage 6b is open to the first space 14a in the back pressure chamber via the turning bearing 2e and the main bearing 12. When the lubricating oil 17 at the discharge pressure flows into the first space 14a, the pressure in the first space 14a is equal to or substantially equal to the discharge pressure. Therefore, the pressure gradient between the upper end surface and the lower end surface of the main bearing 12 is almost eliminated,
The refrigerant dissolved in the lubricating oil does not foam under reduced pressure, and high bearing reliability can be obtained.

The lubricating oil 17 flowing into the first space 14a
Means that the minimum necessary amount of the second space 1
4b, lubricating the anti-rotation member 4, such as an Oldham ring, and other sliding parts, is discharged to the compression space 7 through the small holes 11, and most of the remaining lubricating oil in the first space 14a is The air is discharged to the space in the sealed container 10 by gravity through a gap (a bearing gap or a cut surface provided on the crankshaft 6) of the main bearing 12.

On the other hand, a second space 14b in the back pressure chamber communicates with the compression space 7 by a small hole 11 provided in the end plate 2a of the orbiting scroll member 2, and the second space 14b has a discharge pressure and a suction pressure. It is maintained at an intermediate pressure between the pressures. By adjusting the position of the small hole 11 and appropriately selecting the pressure of the compression space 7 to be communicated, the second space 14b
The intermediate pressure can be adjusted to apply an appropriate pressing force to the back surface of the orbiting scroll member 2 with respect to the force for separating the scroll members 1 and 2 from each other. Further, since lubricating oil is not mixed into the compressed gas, there is no need to separate the oil contained in the discharge gas, and a low oil rising amount can be obtained.

FIG. 3 shows another embodiment of the present invention. The difference from FIG. 1 is that an oil discharge passage 18 that opens to the first space 14 a in the back pressure chamber and communicates with the space in the closed casing 10 is provided. By setting the pressure head of the centrifugal pump that guides the lubricating oil 17 to the first space 14a higher than the minimum head necessary to reliably push the lubricating oil 17 to the upper end of the crankshaft 6, the first space 14a Of the lubricating oil 1 flowing into the first space 14a is slightly higher than the discharge pressure.
It is possible to reliably drain the oil 7 from the oil drain 18 to the space inside the closed container 10. In this case, since the oil discharge passage 18 is opened close to the inner wall surface of the closed container 10, the discharged lubricating oil 17 rarely mixes with the flow of the discharge gas in the closed container 10. .

Since the lubricating oil 17 in the first space 14a can be reliably drained, only a minimal amount of the necessary lubricating oil 17 leaks into the second space 14a. The high-temperature lubricating oil 17 is hardly mixed into the compressed gas during compression through the small holes 11 provided in the compressed gas, and the temperature of the compressed gas is hardly increased, so that a decrease in the compression efficiency can be prevented. .

Further, since lubricating oil is not mixed into the compressed gas, there is no need to separate the oil contained in the discharge gas, so that a low oil rising amount can be obtained.

FIGS. 4 and 5 show another embodiment of the present invention. In any case, in the embodiment of FIG. 3, the lubricating oil 17 discharged from the oil drain passage 18 into the space inside the closed container 10 is prevented from being further mixed by the flow of the discharge gas in the closed container 10. It is a structure.

FIG. 4 shows a structure in which an oil drain pipe 19 has one end connected to the oil drain passage 18 and the other end opened to the lubricating oil stored in the bottom of the sealed container 10. is there. The oil drain pipe 19 is provided through a cut surface 5 c provided on the electric motor 5. This allows
The lubricating oil 17 discharged from the first space of the back pressure chamber through the oil discharge passage 18 can be surely returned to the oil sump at the bottom without being mixed into the discharge gas flow in the closed casing 10. Further, in FIG. 5, a partition plate 20 for shutting off the discharge gas flow is provided on the inner wall of the closed vessel 10 between the open end of the oil drainage path 18 into the space inside the closed vessel 10 and the cut surface 5c of the electric motor 5. It is an example. The partition plate 20 and the cut surface 5c of the electric motor 5
Thereby, an oil guide passage is formed.

In each of the embodiments shown in FIGS. 4 and 5, the flow of the discharged gas in the space inside the closed container 10 does not directly interfere with the discharged oil, and the discharge oil is prevented from being mixed with the discharged gas. Therefore, a low oil rise can be achieved.

FIG. 9 shows another embodiment of the present invention. In the conventional scroll compressor, the orbiting scroll 2 has its end plate 2
The frame is supported by the orbiting scroll support portion 3a of the frame and the fixed scroll end plate outer peripheral portion 1e on the outer periphery of a. Also in such a structure, for example, as shown in FIG. 10, the lower end surface of the orbiting scroll boss 2c and the bottom surface 3b of the space forming the back pressure chamber of the frame 3 are used as a sealing surface. First space 14a and second space 14a
Space 14b. In FIG.
Although a plain bearing is used for the main bearing, the back pressure chamber can be similarly divided into two even if a rolling bearing is used.

FIG. 9 shows an example in which the embodiment of the present invention shown in FIG. 1 is applied to a conventional scroll compressor.
5 can be similarly applied, and the same operation and effect as described above can be obtained.

FIGS. 6 and 7 show one embodiment of the sealing member 15 common to all the embodiments. FIG. 6 shows the first space 14a.
A groove 15a is provided on the upper end surface of the seal member 15 as oil leakage means for leaking a minimum necessary amount from the internal lubricating oil to the second space 14b. Back pressure chamber second space 14b
A required amount of lubricating oil 17 can be supplied through the groove 15a to the anti-rotation member 4 such as the Oldham ring and the sliding parts such as the end surfaces of the scroll members 1 and 2 in FIG. By adjusting the number, width and depth of the grooves 15a,
The supply amount of the lubricating oil 17 can be controlled. If the amount of lubricating oil leaking from the first space 14a in the back pressure chamber to the second space 14b through the upper end surface of the seal member 15 is sufficient depending on the processing accuracy, the groove 15a may be omitted. Good.

FIG. 7 shows an embodiment in which a notch 15b is provided in the seal member 15. The first space inside the seal member 15 is substantially at a discharge pressure, and the second space outside the seal member 15 is at an intermediate pressure, which is intermediate between the discharge pressure and the suction pressure. Accordingly, the seal member 15 receives a force due to the pressure difference from the inside to the outside and is deformed as shown in FIG. Here, as shown in FIG.
Is provided, it is possible to adjust the diameter of the seal member 15 without deteriorating the sealing performance in response to the deformation when receiving the force due to the pressure difference. The property becomes good.

[0031]

As described above, according to the first to fifth aspects of the present invention, the first space on the center portion side is sealed by the seal member provided between the orbiting scroll member and the claim. And a second space on the outer peripheral side,
The lubricating oil in the first space under the discharge pressure is guided through the oil drain pipe to the bottom of the closed vessel below the electric motor without being mixed with the compressed gas in the closed vessel.
Since the structure is such that lubricating oil does not flow into the space above the minimum necessary amount, a scroll compressor having a small amount of lubricating oil (oil rising amount) mixed into the discharge gas can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a scroll compressor showing one embodiment of the present invention.

FIG. 2 is a partially enlarged view showing a seal portion of one embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a scroll compressor showing another embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a scroll compressor showing still another embodiment of the present invention.

FIG. 5 is a longitudinal sectional view of a scroll compressor showing another embodiment of the present invention.

FIG. 6 is a view showing a seal member according to one embodiment of the present invention.

FIG. 7 is a view showing a seal member according to another embodiment of the present invention.

FIG. 8 is a partially enlarged view showing a seal portion of one embodiment of the present invention.

FIG. 9 is a longitudinal sectional view of a scroll compressor showing still another embodiment of the present invention.

FIG. 10 is a longitudinal sectional view of a conventional scroll compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Fixed scroll member 1a ... End plate 1b ... Fixed scroll wrap 1c ... Discharge port 1d ... Keyway 2 ... Revolving scroll member 2a ... End plate 2b ... Revolving scroll wrap 2c ... Boss part 2d ... Keyway 2e ... Revolving bearing 3. Frame 4 ... rotation prevention member 5 ... motor 5a ... stator 5b ... rotor 6 ... crank shaft 6a ... crank pin 6b ... oil supply path 7 ... compression space 8 ... suction pipe 9 ... seal bearing 10 ... closed vessel 11 ... small hole 12 ... main bearing 13 ... Bolt 14 ... Back pressure chamber 14a ... First space 14b ... Second space 15 ... Seal member 15a ... Groove 15b ... Notch 16 ... Discharge pipe 17 ... Lubricant oil 18 ... Drainage path 19 ... Drainage pipe 20 ... Partition Board

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kenji Tojo 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Inside Air Conditioning Systems Division, Hitachi, Ltd. (72) Inventor Hideyuki Ueda 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Air Conditioning Systems Business, Hitachi, Ltd. Internal F-term (Reference) 3H029 AA02 AA14 AB02 AB03 BB03 BB41 CC17 CC19 CC22 CC32 3H039 AA03 AA06 AA12 BB11 CC24 CC27 CC31 CC41

Claims (5)

[Claims] An electric motor and a scroll compression mechanism are housed in a closed vessel, and the inside of the closed vessel is communicated with a discharge port to maintain the pressure in the closed vessel at a discharge pressure, while a back side of the orbiting scroll member is positioned on a side opposite to the wrap side. In a scroll compressor having a pressure chamber, a seal member is provided between a frame fixed to the fixed scroll member and the orbiting scroll member, and the seal member allows a pressure substantially equal to a discharge pressure in a central portion to be provided. A first space in which an oil supply passage through which lubricating oil stored in the bottom of the closed container is guided is opened, and a pressure between the suction pressure and the discharge pressure in the outer peripheral portion is maintained. A second space, wherein the seal member is held by the frame,
In addition to sealing between the upper end surface of the seal member and the opposite wrap side surface of the orbiting scroll member, sealing is also performed between the outer peripheral surface of the seal member and the ring-shaped groove, and lubricating oil in the first space is removed. An oil drain pipe is provided for returning to the bottom of the closed container without mixing with the compressed gas in the closed container, and the lower end of the oil drain pipe is extended and opened to the bottom of the closed container below the lower end of the electric motor. A scroll compressor characterized by the following. 2. A head plate, a revolving scroll member and a fixed scroll member comprising a spiral wrap standing upright on the head plate are meshed with each other with the wrap inside, and a compression space formed by both scroll members is centered. Move to
A scroll compression mechanism that performs relative movement of the two scroll members so as to reduce the volume is housed in a sealed container, and the inside of the sealed container is communicated with a discharge port to maintain the pressure in the sealed container at the discharge pressure, while the orbiting scroll member. In a scroll compressor having a back pressure chamber on the side opposite to the lap, a seal member is provided between the orbiting scroll member and the frame, and the seal member has a pressure substantially equal to the discharge pressure in the center portion. And a first space in which an oil supply passage through which lubricating oil stored in a bottom portion of the closed container is guided upward is opened, and a second space is formed in an outer peripheral portion of the seal member. Is held by the frame,
In addition to sealing between the upper end surface of the seal member and the opposite wrap side surface of the orbiting scroll member, sealing is also performed between the outer peripheral surface of the seal member and the ring-shaped groove, and lubricating oil in the first space is removed. An oil drain pipe is provided for returning to the bottom of the closed container without mixing with the compressed gas in the closed container, and the lower end of the oil drain pipe is extended and opened to the bottom of the closed container below the lower end of the electric motor. A scroll compressor characterized by the following. 3. A head plate, a revolving scroll member and a fixed scroll member, each of which is composed of a spiral wrap standing upright on the head plate, are engaged with each other with the wrap inside, and a compression space formed by both scroll members is centered. Move to
A scroll compression mechanism that performs relative movement of the two scroll members so as to reduce the volume is housed in a sealed container, and the inside of the sealed container is communicated with a discharge port to maintain the pressure in the sealed container at the discharge pressure, while the orbiting scroll member. In a scroll compressor having a back pressure chamber on the side opposite to the lap, a seal member is provided between the orbiting scroll member and the frame, and the seal member has a pressure substantially equal to the discharge pressure in the center portion. And a first space in which an oil supply passage through which lubricating oil stored in a bottom portion of the closed container is guided upward is opened, and a second space is formed in an outer peripheral portion of the seal member. A force corresponding to the pressure difference between the first space and the second space is applied from the lower side to the upper side to cause a force between the upper end surface of the seal member and the non-lap side seal surface of the orbiting scroll member. At the same time, a seal is formed between the outer peripheral surface of the seal member and the frame, and the minimum necessary amount of lubricating oil leaks from the first space to the second space via the seal member due to a differential pressure. A scroll compressor, wherein an oil drain pipe is provided for returning most of the remaining lubricating oil in the first space to the bottom of the closed container below the electric motor. 4. A pressure head that opens into the first space and communicates with the space in the closed container is formed in the frame, and a pressure head that guides the lubricating oil to the first space is used to reliably supply the lubricating oil. The head is set higher than the minimum required for pushing up to the upper end of the crankshaft, so that the lubricating oil flowing into the first space can be surely drained from the oil drain to the bottom in the closed container. The scroll compressor according to any one of claims 1 to 3, wherein: 5. The frame according to claim 1, wherein a groove for holding the seal member is provided in the frame.
A scroll compressor according to any one of the above.